


Back for more

by mellyface



Category: Uta no Prince-sama
Genre: Anal Sex, Blow Jobs, Casual Sex, M/M, PWP, but then kinda also does cause he wants Ai to enjoy it too, good stuff, ranmaru knows ai is a robot but doesn’t really care
Language: English
Status: Completed
Published: 2019-08-08
Updated: 2019-08-08
Packaged: 2020-08-12 23:53:38
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 3,402
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/20164705
Author URL: https://archiveofourown.org/users/mellyface/pseuds/mellyface
Summary: —so, can robots have sex?Ranmaru asked if he’d done it. Ai had said no. Was he curious? Ai said, yes, a little.—(In which it turns out trying sex with Ranmaru just once isn’t enough for Ai)





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**Author's Note:**

> My first fic in like 1039393 years...amazing  
I can’t believe I got into utapri and have all these emotional reiai FEELINGS and then just wrote dumb cute ranai sex  
Every combination of QN (and the other characters) is good tho tbh
> 
> Sorry I wrote the majority of this in one go and didn’t proofread but I’ll try and go back and fix mistakes later it’s like midnight rn im sleepy
> 
> Enjoy!!!

Ranmaru flings the bedroom door open with a sturdy kick and stumbles in, Ai in tow. He hoists the android over his hip, forearms flexed under the curve of his ass, their mouths never leaving each other’s for more than a brief second. 

Ai’s heavier than he looks—makes sense figuring the whole robot thing—but nothing too heavy for a strong guy like Ranmaru to lift. Carrying him from the living room couch to his bed is no sweat off his back, and plus Rock and Roll as hell. He slams the door behind him without wasting a glance, quickly resuming his grip on Ai’s ass. Ai, in turn, comfortably wraps his limbs around Ranmaru’s waist and shoulders and helps himself to more kisses with unabashed eagerness.

It started not too long ago, with a question of simple, albeit blunt, curiosity from Ranmaru

—_so, can robots have sex? _

Ai had explained matter-of-factly that the craving for it wasn’t there like in humans but yes, in the interest of his body being otherwise as humanlike as possible, he was capable of a number of functions, sex included. Ranmaru asked if he’d done it. Ai had said no. Was he curious? Ai said, yes, a little.

A little turns into a lot. Trying it only once, it turns out, isn’t enough to sate Ai’s curiosity, and for all he’s said robots don’t crave it like humans do, he sure doesn’t seem to be able to get enough of it.

Not that Ranmaru has any problem with this, Ai may not have normal human cravings but Ranmaru does, and maybe the whole sticking his dick in a robot thing is a little weird if he thinks too much about it, but sex with Ai is easy, and—if he’s being honest—pretty damn good. 

He tosses Ai onto the mattress, receiving only a slight frown for his rough-handedness before he’s pulled down on top of his groupmate. The thing about Ai is that he learns how to do things perfectly almost scarily fast, and even though the first time they’d done this he’d been kind of a shit kisser, he’s already gotten unfairly good. Ranmaru can’t help letting a low, muffled growl escape into Ai’s unrelenting mouth when he feels cool fingers scratch pleasantly at the base of his neck and then tug firmly at his scalp. The burn of both arousal and his own ego flares hotly in his veins—it’s kinda annoying if this punk 8 years his junior shows him up, isn’t it.

“Your heart rate has increased by 30 beats per minute.”

Well the bedroom talk could still use some work, Ranmaru thinks, to what he’s not sure he would consider either his relief or dismay.

“Yeah, well I just lifted your heavy ass all the way from the living room.” he growls, not particularly perturbed in spite of his complaints, actually much more fixated on biting sweet little marks onto Ai’s pale neck, “how bout you check your own heart rate then, huh?”

“I don’t have an organic heart, so—”

“You know what I mean.” Ranmaru slides his hands up Ai’s shirt and feels his smooth, slim belly under his fanned out fingers. He curls them inward and claws lazily over the pretty, taut skin—breathes against Ai’s ear, “Don’t go overheatin’ on me, or say somethin’ if you’re about to. Don’t wanna fuck someone who’s unconscious.”

Ai stares at him, unamused, “You don’t mince words as usual, Ranmaru.”

“Heh. Like you’re one to talk.”

“Understood, I’ll say something if I feel like I might overheat.”

Ranmaru just grunts in thanks and closes his mouth back over Ai’s. Annoyingly ever-skyrocketing kissing skill aside, it’s pretty cute that he’s surprisingly needy. When Ranmaru slides his tongue back between Ai’s lips, Ai sucks on it hungrily and his hands tangle up in Ranmaru’s wild silver hair. The rocker grins into the kiss, biting at Ai’s lips while rubbing and teasing at his chest.

Maybe someone else would wonder—maybe it would make more sense for him, too, to be more curious about how robots work and which parts of Ai’s body are organic or synthetic and how and why they do or don’t function like a typical human’s, et cetera, but for Ranmaru that shit’s pretty irrelevant. All he thinks is, _ Nice_, Ai is really sexy while having his nipples played with. _ How _he’s feeling it doesn’t really matter so much when he’s clearly feeling it, squirming under Ranmaru’s thumbs and forefingers, turning pink in the face and saliva dripping down his chin when he wrests free from jaw-aching kisses to let out a sweet little moan. 

_ Yeah, more of that, _ Ranmaru thinks and twists and pulls harder, enjoying how Ai’s slim but heavy body shakes the whole bed whenever he writhes.

“Ranmaru—!” Ai huffs. 

“What,” Ranmaru lulls with a stupid grin, “Don’t tell me you’re overheatin’ already.”

Ai throws his bandmate a displeased look over his shoulder, having only barely struggled onto his side in an attempt to escape.

“I’m not.”

Ranmaru smirks. It’s always kinda fun seeing Ai like this, all flushed and jittery—still cheeky as hell though. But then again if he wasn’t, it wouldn't be Ai.

Ranmaru keeps one hand rested on Ai’s hip, reaching up to thumb away the string of drool from his bottom lip with the other. Pretty interesting that he doesn’t get hungry, but still can salivate—though it’s true it would be noticeable and look pretty damn strange up close if his mouth wasn’t wet. After all Ai doesn’t only have to function as a human but in physical terms also visibly pass as one.

It definitely looks sexy too, his lips wet and kissed red and swollen, his tongue pink and shiny in his mouth. Ranmaru gets an idea. He sits back on his haunches on the bed, sporting a pretty noticeable erection at this point that he doesn’t feel particularly ashamed of.

“How about you suck me off.”

Ai immediately makes a face, “No.”

“_Hah—_?!” Ranmaru feels heat rise up to his ears, obviously not having expected to be flat out rejected.

“It sounds unpleasant, besides there’s nothing pleasurable in it for me.”

Ranmaru almost grins at that, this fucking brat, seriously—

“Tch. You’re not even curious what it tastes like or anything...?” 

Ai stares at him contemplatively, considering Ranmaru’s challenge. The way Ai doesn’t even blink makes him almost feel a little self conscious. He doesn’t really want to get rejected a second time for wanting his dick sucked.

_ Maybe you’ll like it_, he opens his mouth to offer as a half-assed last resort, but amazingly enough Ai renders his unspoken plea unnecessary for the time being at least, with a tuck of light-blue hair behind his ear and a slow thoughtful nod. He’s considering it.

“I would imagine it just tastes like skin, maybe salty—is that not true?”

The fuck if I know—Ranmaru thinks immediately. Like hell he’s sucked anyone’s dick before. It’s not like Ai’s the first male bodied person he’s ever hooked up with, but. Still he bites his tongue.

“Don’t know unless you try huh.” 

It’s a pretty stupid challenge but this kind of stuff works on Ai, who makes another unpleasant face but also knows he’s been cornered. As a data collecting machine, empiricism is his weakness. 

He makes a point of sighing to show Ranmaru he hasn’t fooled anyone, but he resigns himself and sits up properly. Ranmaru finds he misses the sight of Ai’s stomach as soon as his shirt slides back down to hide it.

“Remove your pants and undergarments then.”

He has to snort at the way Ai says it like this is a trip to the doctor’s office and not foreplay, but lets it slide. He’s not in any position to make snide remarks when he’s about to get his dick sucked. He kicks off his pants in silent, if not a bit eager compliance. It’s even more obvious than it already was how hard he is, and the feeling of cool air on his pelvis when all the blood is rushing there is admittedly not his favorite.

Ai repeats the same motion of tucking his hair behind his ear despite it already being tucked out of the way, habitually prim, and leans down between Ranmaru’s thighs. He has only half a second to think Ai’s opened mouth is small and cute and honestly a little erotic before a warm stripe along his length sends a tiny but fierce electric jolt to his brain. Ohh man. It’s been awhile.

Ai peeks up at him, tongue still lewdly pressed flat to the base of Ranmaru’s cock almost like a tongue frozen to a popsicle.

“It’s salty.” He confirms, drawing it back into his mouth but not without licking his own lips first. Robots are faster at processing taste than Ranmaru had thought. Or maybe it’s not the taste but a sampling of chemicals in his physical makeup or whatever.

He pushes the unsexy thought away and narrows his eyes suspiciously.

“Please don’t tell me you’re done already.”

Ai replies not with words but with another lick up his swollen cock, fuller this time and to the tip. Ranmaru hisses softly. _Thank fuck_.

Ai does it again, and then again and while he’s grateful for anything at all considering Ai’s initial reluctance he feels like he’s probably going to lose it if Ai keeps lapping at him without putting that mouth on him properly.

“Ai,” he growls softly, and runs his fingers through the loose side of his hair, knowing he likes to be touched. He kind of uses the motion as an excuse to tilt Ai’s head back and rub his dick against his lips. That’s a pretty damn erotic sight, and Ranmaru feels his pulse quicken.

“Your heart rate just—”

He feels a tiny bit bad but takes the opening nonetheless to slide his cock past Ai’s lips. Ai stills in surprise but his eyes widen just a bit.

“Just a little,” he breathes. It’s been so long, and while Ai’s mouth is strangely warm rather than hot like a human’s, it’s soft and wet and inviting and pretty. Seeing his thing slide past those shiny pink lips which may as well be real and human definitely does something hot and funny deep in the lower part of his belly.

Ai doesn’t respond—probably can’t, though Ranmaru isn’t exactly confident on that, with a dick in his mouth—but simply continues to run his tongue curiously all over the length of Ranmaru’s cock, only this time within the slick, wet, lovely confines of his mouth. Ranmaru closes his eyes and his breathing becomes just the barest hint of audible.

Ai follows along in tune with the signals he receives from Ranmaru’s body. Another reason why he’s quickly become so annoyingly good at all of this is the unfair advantage of being able to read Ranmaru’s stats like he’s hooked up to a machine. Well in a weird way right now he supposes he kind of is. But thanks to that he knows exactly what to do more of, the way Ranmaru’s pulse suddenly thrums louder or muscles contract or breath becomes labored, all telling signs—and he glances up at Ranmaru with a curious look as if to say, _ you like this don’t you? _

_ You sure as hell bet I do_. His eyes gleam back in response, but he squeezes them shut quickly when Ai’s tongue flattens over the slit of his cock.

Unfortunately Ai being able to read his body also means he can tell when Ranmaru’s about to come—which enables him to pull off cruelly just soon enough before his orgasm has a chance to fully actualize.

Ranmaru bites off a curse.

“I don’t want that in my mouth.” Ai explains without being asked. _ That _ obviously meaning Ranmaru’s ejaculate.

_ Yeah? Where do you want it then? _ Ranmaru wants to taunt but he’s honestly too busy reeling in the light headedness of denial.

When the feeling dissipates and some clarity returns to his head what he thinks instead is, _ fair enough. _

“So how was it?” he asks instead. Might as well learn just exactly what his chances are of getting that again, at least from Ai, anyway.

“It wasn’t terrible. But I wouldn’t call it pleasant.”

Ranmaru nods, decidedly okay with those odds. He pats Ai on the head, but ends up just kind of feeling his silky hair. He pulls it gently down from its half-updo, mussing it and smoothing it, stroking him in what maybe admittedly is a bit of affection—people do tend to become cuter to you when you’re continuously having sex with them. Especially if they’ve also sucked your dick now as well. 

Ai just watches Ranmaru and lets his hair be messed with. Ranmaru withdraws his hand to card it stiffly through his own spiky silver strands instead.

“‘Kay, I’ll do somethin’ for you now, then. Fair’s fair.”

Ai leans back and shrugs, “I’m fine. Let’s just have sex.”

He doesn’t waste any time in removing his own shirt, followed by his pants. Ranmaru snorts softly but he isn’t gonna argue with that. It only takes a little digging to find a condom and some lube in a recess in his bedside drawer. 

While it’s arguably still a little early to roll on the condom, it does help take off some of the immediate edge, dulling his senses and making it easier to push Ai onto his back, spread his legs and unceremoniously dump a generous squirt of shiny lube all over his hole. 

He probably doesn’t need that much—if anything it’s mostly just for Ranmaru’s sake going in easier without any painful friction—but damn, he can’t help thinking it looks kinda really hot.

Ai’s stomach sucks in and his dick gives a little twitch, amazingly humanlike as Ranmaru stuffs his first finger in. He wiggles it around without much worry for Ai’s comfort, just focusing on stretching him open. Just as well, pain being no issue, Ai already seems to be feeling it as his eyelids flutter and pretty hum escapes him one after another. Ranmaru’s eyes flicker up to watch what absolutely has to be real pleasure distort Ai’s expression while he presses in a second and then a third in quick succession. How much is a program and how much is actually real, he has no idea, but even if it’s all just a program thinking of it as an extremely advanced interactive porno isn’t so bad.

Or so he tells himself, but he finds he honestly really wants Ai to genuinely enjoy it.

“Ai.”

He leans up to steal a kiss, pushing Ai’s thigh to the side with his knee so he can free a hand to feel at his torso. He drags his fingertips up Ai’s smooth side to play with his chest again, feeling the younger jolt at the unexpected assault of sensations. Ai bites at his lip kind of hard and Ranmaru sucks in a hiss that’s more surprised than pained, and rubs harder at Ai’s insides in retaliation, the force of his arms driving his backside further down into the mattress. The android grasps at his shoulders for purchase.

“Ran...maru!” Ai gasps, grip turning into blunt claws. The white marks on Ranmaru’s shoulders bloom into a quickly deepening pink.

“Yeah,” he breathes, more turned on than he should be considering he hasn’t been touched in some few solid minutes. 

His dick aches, honestly, to be buried deep in Ai, and it’s not like there’s really any need to wait, so why? But he can feel Ai unraveling under his weight, hips swiveling in confusion between a desire to escape or desperation for more, smothering pleasure. He feels Ai’s cock twitching against his own stomach as he presses their bodies together, runs his tongue along the meat of Ai’s pretty neck where his pulse would surely be thudding if he had one. He can almost hear it anyway, he swears. He twists his fingers to earn another easy moan, more raw and ragged than any tune Ai’s ever sung but just as beautiful. There’s no way it’s all solely just some program—if it was, why would Ai keep coming back for more?

“Hurry…” even with a quiver in his voice, Ranmaru knows it’s less of a plea and more of a command—Ai remains a cheeky brat to the end. 

“You don’t gotta tell me,” he breathes, his voice low and with the barest hint of a shaky laugh. He gives Ai another sloppy, hurried kiss before easily pushing him over onto his stomach and lining up his cock, free thumb still pulling, spreading Ai’s sweet hole. 

“Raise your hips.” 

Ai obliges, and Ranmaru sinks in. He wastes no time burying deep to the hilt, til he hears the smack of his skin on Ai’s. The robot can take it.

All he hears is Ai’s muffled hum of approval, face down against his mattress. Ranmaru’s nails rake their way up his spine and into his pretty hair, alternating between sifting gently and the occasional mildly possessive tug.

He works up a steady and fast rhythm, gripping Ai’s hip just about as hard as Ai grips the sheets, slamming his own hips hard into the small but heavy frame bent beneath him. He hunches over as pleasure bubbles hot inside him, but takes the opportunity while he’s down to drag his lips and occasionally teeth over the smooth white expanse of Ai’s back.

“Ranmaru, Ranmaru…,” Ai repeats tirelessly, and the rocker enjoys the thrill of his own name in his ears with each heavy snap of his hips.

“Ai,” he’s more than happy to answer back, his hand snakes around Ai’s front once more to pinch and pull at his chest, earning a satisfying shiver and a spasm.

“So good…” he grunts, going as hard and fast as he wants with no consequence, only benefit, “you close?”

Ai doesn’t answer, only buries his face deeper into the pillow with another poorly muffled moan.

“Ngh, yeah, me too…” Ranmaru grinds out, feeling sweat drip down the back of his neck and his skin sticking to Ai’s whenever he pulls back his hips. With one more good thrust he empties into the condom, kinda honestly wishing it was into Ai instead but realistically not knowing what complications that might cause. He milks his own orgasm with a few final smaller thrusts, buries his face between Ai’s shoulder blades and desperately rubs and tugs round front at his cock to draw out Ai’s as well before he inevitably becomes too tired to give a damn.

For whatever reason, maybe again the sake of appearing human, Ai does always climax in a realistic fashion, something slimy dribbling cutely out of his dick and all over Ranmaru’s hand that sure looks and feels like but for sure cannot be real cum. Just as well, it feels satisfying and “right” to end this way, so Ranmaru never questions it.

He rolls off of Ai and onto his own back, too sated to give a damn about being sweaty or having mysterious robot jizz on his hand. His own condom has been removed and tied off and cast somewhere hopefully at least remotely close to the waste bin in the corner. 

He breathes a contented sigh.

“Hell yeah.”

Ai smiles at him over his shoulder, an expression between contentment and amusement, if not a little judging for Ranmaru’s choice of words. 

Ranmaru feels the look pointed at him, tears his sleepy gaze from the ceiling to scan Ai’s face, and body language, curled up cozy on the bed despite that he didn’t feel things like fatigue or sleepiness. Yeah, he’s definitely cute.

_ You liked that, right? _ he finds himself wanting to ask. He’s never been one to doubt his performance in anything, that’s not what this is about. But either way he doesn’t ask. 

Instead, to his surprise, Ai opens his mouth to speak, in blank, complete earnest.

“I liked that. Let’s do it again sometime.”

Ranmaru turns his head back to the ceiling, flinging a lazy arm over his face as his lips quirk into a funny smirk. What the heck. 

The skin on his face feels warm against his arm.

“Yeah. Sure thing.”

**Author's Note:**

> I never know how to end pwp fics I’m so sorry


End file.
